These seaduck breed on freshwater lakes and were in Northern Scotland in very small
numbers 100 years ago. Now Caithness and Sutherland probably have more than half the breeding
birds. In Ireland a colony at Lower Lough Erne, established 1905, peaked at 150 pairs (1967) and
was extinct by 1995, when the three other Irish colonies held up to 110 pairs.
Eutrophication of the Irish lakes is a grave problem and feral mink predation a real threat.